Fault Finding; Safety Regulations; Fault Finding Procedure; Operating Conditions - Grundfos CUE Series Service Instructions Manual

3. Fault finding

The operational status of CUE and faults are automatically shown
via the indicator lights and the display of the operating panel.
If the alarm light is on, the display shows a code with text which
gives information of the cause. See

3.1 Safety regulations

WARNING
Electric shock
Death or serious personal injury
- Do not use the OFF button on the operating panel
as a safety switch.
- All service work must be carried out by trained
persons.
- Due to the capacitors of CUE, touching the
electrical parts may be fatal, even after the mains
supply has been switched off.
- Switch off the mains supply, and wait at least as
long as stated on the nameplate before touching
electrical parts.
- Note that the relay may be connected to an
external voltage supply and still be current-
carrying even after the mains supply has been
disconnected.

3.2 Fault finding procedure

Fault diagnosing and fault correction is based on these sections
in this order:
•

3.3 Operating conditions

•
3.4 Fault finding using alarm and warning
Startup guide
The startup guide
• is started the first time CUE is connected to supply voltage
• can be started in [Favourites] > "Q4" > "Run startup guide"
• will start if CUE is reset to the factory setting.
If CUE is in alarm state, you must carry out fault finding based on
the alarm code before activating the startup guide, if necessary.
An alarm may be caused by wrong settings!
Resetting to factory setting
Before resetting CUE to the factory setting, get a complete
overview of the settings and possible functions required by CUE.
To reset CUE to factory setting, proceed as follows:
1. Switch off the mains supply to CUE.
2. Switch on the mains supply to CUE while you press [Status],
[Main menu] and [OK] simultaneously for at least 3 seconds.
When CUE has been reset to factory setting, go through the
startup guide.
Contacting Grundfos
State these pieces of information when you contact Grundfos to
get help for fault finding:
• nameplate data of the pump or system which CUE controls or
is part of
• nameplate data of CUE
• status of the indicator lights on the operating panel
• any alarm or warning text and the code number on the display.
3.4.1 Alarm and warning list.
codes.
3.3 Operating conditions
CUE is the controlling unit and will react and control the pump
depending on the following:
Mains supply
• Check nameplate data, and measure the actual voltage supply
with a voltmeter (true RMS).
• Check the earth leakage circuit breaker and the backup fuses.
CUE has no internal fuses.
Pump and motor load
• Check nameplate data, and measure the actual current
consumption with an amperemeter (true RMS).
Does the pump and CUE match?
External signals, for instance from another controller
• Check that the external signals match CUE. See section
2.4.2 Wiring diagram, signal terminals
installation and operating instructions.
• Check that terminals 18 and 20 are connected and CUE has
been started via the operating panel.
Sensors connected
• Check that the sensor measuring range matches the pump
application.
• Check that the settings of CUE match the sensors (current,
voltage, minimum and maximum values).
Electromagnetic disturbances
• Check that the cable run is EMC-correct. See the CUE
installation and operating instructions.
Startup, installation and operating settings are made via the
operating panel.
• Check whether the signal indicator On on the operating panel
is lit.
• Go through the startup guide at startup. If the startup guide is
activated later on, the settings made will be reset. Set CUE to
the correct values for the pump application. The startup guide
is described in detail in the CUE installation and operating
instructions.
• Check that the settings in the installation menu match the
pump application. (The displays are described in detail in the
CUE installation and operating instructions.)
• Check the status display of the operating panel if the pump
has stopped.
If the above items are according to the CUE installation and
operating instructions and the pump application, but a fault still
exists, continue the fault finding in section
alarm and warning codes.
and the CUE
3.4 Fault finding using
7